From: Francois-Xavier Le Bail <devel.fx.lebail@orange.fr>
Date: Tue, 15 Oct 2024 19:08:57 +0000 (+0200)
Subject: Update the ND_TCHECK_LEN macro definitions
X-Git-Url: https://git.tcpdump.org/tcpdump/commitdiff_plain/6fa624334bfa077934deb08b65ffbd22105429e1

Update the ND_TCHECK_LEN macro definitions

Avoid warnings such as in the following case:

        if (...)
                ND_TCHECK_LEN(...);
        else

With gcc:
source.c:X:12: warning: suggest explicit braces to avoid ambiguous
  'else' [-Wdangling-else]
    X |         if (...)
      |            ^

With clang:
source.c:Y:2: warning: add explicit braces to avoid dangling else
  [-Wdangling-else]
        else
        ^
---

diff --git a/netdissect.h b/netdissect.h
index 62383e65..2bd4cfd7 100644
--- a/netdissect.h
+++ b/netdissect.h
@@ -386,9 +386,15 @@ NORETURN void nd_trunc_longjmp(netdissect_options *ndo);
 
 /* Bail out if "l" bytes from "p" were not captured */
 #ifdef ND_LONGJMP_FROM_TCHECK
-#define ND_TCHECK_LEN(p, l) if (!ND_TTEST_LEN(p, l)) nd_trunc_longjmp(ndo)
+#define ND_TCHECK_LEN(p, l) \
+do { \
+if (!ND_TTEST_LEN(p, l)) nd_trunc_longjmp(ndo); \
+} while (0)
 #else
-#define ND_TCHECK_LEN(p, l) if (!ND_TTEST_LEN(p, l)) goto trunc
+#define ND_TCHECK_LEN(p, l) \
+do { \
+if (!ND_TTEST_LEN(p, l)) goto trunc; \
+} while (0)
 #endif
 
 /* Bail out if "*(p)" was not captured */